Proxy computer system to provide direct links for bypass

ABSTRACT

A proxy computer system makes a determination as to whether a link, provided with content retrieved from a third-party network service, locates a corresponding resource that is of a preselected set of one or more types. If the corresponding resource located by the link is of the preselected type, the system structures the link as a direct link that is selectable by the requesting client computer to bypass the proxy service and to directly retrieve the corresponding resource from the third-party network service.

RELATED APPLICATIONS

This application Claims benefit of priority to Provisional U.S. PatentApplication No. 62/419,960, filed on Nov. 9, 2016; the aforementionedpriority application being incorporated by reference in its entirety forall purposes.

BACKGROUND

Cloud, SaaS and web applications are increasingly adopted byenterprises. Using hosted services can expose security issues due to thefact that these services typically store information (oftenconfidential) outside the corporate firewall. This shift towards cloud,SaaS and web applications has forced enterprise to search for mechanismsto independently secure these systems. In securing these systems,enterprises are using Suffix Proxy servers. The major constraint withsuffix proxy servers is that as remote infrastructure changes locationand subdomains, additional SSL certificates are required. Forcomplicated cloud, SaaS and web applications the number of certificatesor certificate subject alternative names can be extensive. In addition,SSL certificate infrastructure only allows a single level of wildcardcertificate. This means that secure communications can be impossiblewithout a certificate for every possible combination of URL subdomains.Complex geographically distributed applications make extensive use ofsubdomains for traffic routing, load balancing and redundancy. Toeffectively suffix these services, some conventional approaches requirethat an enterprise must know in advance every possible subdomain andhave a certificate or entry within the certificate for every possiblecombination.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an example proxy computer system, according to one ormore embodiments.

FIG. 2 illustrates an example method for operating a proxy service toenable client computers (including servers) to utilize a third-partynetwork service.

FIG. 3 illustrates a proxy server system that implements content controlwith respect to access by client computers of a third-party networkservice.

FIG. 4 illustrates an example method for operating a proxy service toselectively decrypt content returned by a third-party network service.

FIG. 5 illustrates an example method for operating a proxy service toselectively provide direct links for client computers to bypass theproxy service.

FIG. 6 is a block diagram that illustrates a computer system upon whichembodiments described herein may be implemented.

DETAILED DESCRIPTION

Examples provide a proxy server system for use with clients that utilizenetwork services. The proxy server system enables, for example,enterprise networks to utilize enhanced or ancillary services of theproxy server system in connection with the third-party network services.Through operation of the proxy server system, the number of distinctdigital certificates which third-party network services typicallyrequired by clients is significantly reduced. Moreover, the proxy serversystem enables the client to receive the services of the third-partynetwork service, without requiring configuration on the client through,for example, execution of scripts.

In some examples, a proxy server system operates to parse, structure andre-structure Uniform Resource Locators (URLs) which are provided from orfor use with the third-party service. Among other functionality, theproxy server system replaces and constructs syntax for the URLs in amanner that reformats the individual URLs to have a common network levelor wildcard designation. The proxy server system may perform translationoperations so that clients utilize re-structured (or packed) links,while the third-party network service receives and generatesde-structured or non-structured (or unpacked) links. The translationoperations performed by the proxy server system may be transparent toboth the client and to the third-party network service.

In some examples, the proxy server system encodes a destination of thethird-party network service into an incoming request link from a client.The proxy server system 100 may also reconstruct the incoming requestlink to have the native structure of the third-party network servicebefore sending the re-structured link to the third-party service. Forlinks which are provided from the third-party network service, the proxyserver system can structure the individual links from the nativestructure to an alternative structure of the proxy server system. In thealternative structure, the URL eliminates syntax that designatessubdomains and multiple network levels, so that the URL is flattened andcan accommodate a common wildcard designation. The proxy server systemcan also perform the translations for links provided by the third-partynetwork service, so that a requesting client is able to receive thefunctionality provided through the provided links and accompanying data,without the client needing multiple SSL certificates which may otherwisebe required from the third-party network service.

According to some examples, a proxy computer system uses at least aproxy-specified certificate, to receive one or more request links fromthe client, the one or more request links having a proxy domain format.The proxy computer system translates the one or more request links fromthe proxy domain format into a native structure for the third-partynetwork service. The proxy computer system further communicates with thethird-party network service using (i) the translated one or more requestlinks, and (ii) multiple certificates that are required from thethird-party network service to receive a particular data set.

According to some examples, a proxy computer system receives contentintended for a client computer from a third-party network service, wherethe content includes an encrypted portion. The proxy computer systemmakes a determination as to whether the encrypted portion is to bedecrypted for the client computer, where the determination is made basedat least in part on a historical analysis of the client computer. Theproxy computer system sends the content to the client computer in a formthat is based on the determination.

In variations, a proxy computer system makes a determination as towhether a link, provided with content retrieved from a third-partynetwork service, locates a corresponding resource that is of apreselected set of one or more types. If the corresponding resourcelocated by the link is of the preselected type, the system structuresthe link as a direct link that is selectable by the requesting clientcomputer to bypass the proxy service and to directly retrieve thecorresponding resource from the third-party network service.

One or more examples described herein provide that methods, techniques,and actions performed by a computing device are performedprogrammatically, or as a computer-implemented method. Programmatically,as used herein, means through the use of code or computer-executableinstructions. These instructions can be stored in one or more memoryresources of the computing device. A programmatically performed step mayor may not be automatic.

One or more examples described herein can be implemented usingprogrammatic modules, engines, or components. A programmatic module,engine, or component can include a program, a sub-routine, a portion ofa program, or a software component or a hardware component capable ofperforming one or more stated tasks or functions. As used herein, amodule or component can exist on a hardware component independently ofother modules or components. Alternatively, a module or component can bea shared element or process of other modules, programs or machines.

Furthermore, one or more examples described herein may be implementedthrough the use of instructions that are executable by one or moreprocessors. These instructions may be carried on a computer-readablemedium. Machines shown or described with figures below provide examplesof processing resources and computer-readable mediums on whichinstructions for implementing examples described herein can be carriedand/or executed. In particular, the numerous machines shown withexamples described herein include processor(s) and various forms ofmemory for holding data and instructions. Examples of computer-readablemediums include permanent memory storage devices, such as hard drives onpersonal computers or servers. Other examples of computer storagemediums include portable storage units, such as CD or DVD units, flashmemory (such as carried on smartphones, multifunctional devices ortablets), and magnetic memory. Computers, terminals, servers, networkenabled devices (e.g., mobile devices, such as cell phones) are allexamples of machines and devices that utilize processors, memory, andinstructions stored on computer-readable mediums. Additionally, examplesmay be implemented in the form of computer-programs, or a computerusable carrier medium capable of carrying such a program.

FIG. 1 illustrates a computer system for implementing a proxy service,according to one or more embodiments. In an example of FIG. 1, a proxyserver system 100 may be implemented using a server, or combination ofservers, to receive and forward communications between a group of clientcomputers 20 (“client 20” or “clients 20”) and a third-party networkservice 10 (“TPNS 10”). Each of the clients 20 may correspond to, forexample, an end user terminal, server or other computer system capableof communicating with the proxy server system 100 over the World WideWeb and/or other data networks. Among other functionality, the proxyserver system 100 can include or otherwise provide enhanced proxyservice functionality, such as a traffic monitoring component, anencryption component, a security rule and policy enforcement component,and content configuration components. The TPNS 10 may correspond to, forexample, a cloud service, such as a SaaS or cloud service. An example ofFIG. 1 recognizes that, cloud and SaaS services typically requiremultiple levels of subdomains when processing client transactions andproviding access to their respective services. For example, an “Example”service may utilize an “example” domain and further structure theirrespective URLs to specify subdomains (e.g., “system.na1.example.com”).As described with other examples, the third-party network service mayrequire a separate server certificate for enabling access to data setsoriginating from each subdomain identified in the URL.

With respect to an example of FIG. 1, TPNS 10 may generate links for usein connection with its service, where the links have a native structurethat specify multiple levels of subdomain. The multiple levels ofsubdomains may depend on factors such as geographical location andresource requested. By way of example, a typical link generated fromTPNS 10 may correspond to “system.na1.example.com” wherein the “na1”signifies a set of server infrastructure—in this case North America 1.To further the example, TPNS 10 may also utilize“system.na2.example.com” which may signify a second set of serverinfrastructure.

The proxy server system 100 may structure the links for clients 20 in amanner that lessens the need for the client to maintain and utilize SSLcertificates for multiple levels of subdomains. For example, a proxydomain format link provided from the proxy server system 100 maycorrespond to: “systern.na1.example.com.proxy-server.com”.

The aforementioned link includes two levels (“system” and “na1”) thatmay be dynamic. To support the use of dynamic multi-level links in theproxy server system 100, multiple certificates may be needed, to avoidproblems such as certificate warnings and non-renderable portions of apage.

Among other benefits, some examples provide that no end-pointconfiguration is needed for clients 20 which use utilize the proxyserver system 100. Still further, in some examples, the proxy serversystem 100 may be implemented to function with established standards forexchanging communications on IP networks and the Internet. The proxyserver system 100 can generate and provide request links 111 for theclients 20 to utilize in order to access TPNS 10. The request links 111may be structured in a proxy domain format. For example, the individuallinks 111 may include a suffix domain character set that identifies theproxy server system 100, as well as TPNS 10. By way of example, arequest link 111 can correspond to “www.example.com.proxy-server.com”.

In providing a proxy service, the proxy server system 100 may structurerequest links 111 for use by individual clients. During a session, agiven client 20 may initiate a session with the TPNS 10 using one ormore request links 111. During the session, the TPNS 10 may provideresponses 113, which include embedded links 115. The proxy server system100 may receive and handle request links 111 from the client computer20. The proxy server system 100 may receive incoming request links 111from the client computer 20 in a proxy domain format, where the link(e.g., URL) is packed with replacement characters that signify subdomaincharacters. In a given session, the request links 111 which the client20 selects, or has available for selection, re-structured (or packed)links, including re-structured initial request links 111 and sessionlinks 115 (e.g., links provided to user in response to output from TPNS10, such as links embedded in content or responses of TPNS 10). Some orall of the re-structured request links 111 and session links 115 caninclude syntax for enabling a common wildcard designation, such that theproxy server system 100 can exchange communications with the client 20using a single or common wildcard SSL certificate 126.

According to some examples, the proxy server system 100 includes aclient interface 110, a link structuring logic 120, and a serviceinterface 130. Initially, the client interface 110 can provide for theexchange of proxy communications with individual clients 20 in order toprovide proxy services for the proxy server system 100. In particular,the client interface 110 may send and receive re-structured or packedrequest links 111 (as well as session links 115) that can be activatedby the end user browser 20 (e.g., via a browser) to access a givenresource of TPNS 10, through the proxy service 100. The client interface110 may receive and send request and session links 111, 115 that have aproxy domain structure. For example, an incoming request link 111 thatis received by the proxy server system 100 from one of the clients 20may correspond to a Uniform Resource Locator (“URL”) that includessyntax elements which specify a domain of the proxy server system 100.

In the proxy domain format, the individual request links 111 which arereceived from or sent to the client 20 may be formatted to include acharacter or character set that serves as an alternative marker of asubdomain delineation. However, the character or character set areselected to not be recognizable as a subdomain marker to, for example,the browser of the client 20, and the link may be re-structured so thatthe browser can use a single wildcard certificate when sending orreceiving the link. In one implementation, the request links 111, whenin the proxy domain format, include syntax elements which identify theproxy server system 100, as well as TPNS 10. Additionally, in the proxydomain format, some examples include syntax markers (“-” or (hyphen))that are intended to map to character(s) (“.” or (dot)) that arerecognized by TPNS 10 to be delineators for subdomains of the networkspace provided by TPNS 10.

The proxy server system 100 may implement the link structuring logic 120to translate incoming request links 111 and follow on session links 115from the proxy domain structure to the native structure. In thisprocess, each incoming request link 111 is translated into acorresponding request link 121 having the native structure. In oneimplementation, the link structuring logic 120 includes proxy-to-nativelogic 122 which for incoming request and session links 111, 115, (i)parses the individual links for syntax elements that are specific to theproxy service and its domain, and (ii) converts the individual requestand session links 111, 115 from the proxy domain structure to the nativestructure (e.g., unpacks the URLs to eliminate the syntax of the proxyserver domain, replaces the markers for subdomains with characters thatsignify subdomain, etc.).

The proxy-to-native logic 122 removes syntax from any request link 111that is received by the proxy server system 100. In this way, requestlinks 111 which are handled through the proxy server system 100 can besent as request links 121 in the native structure to TPNS 10, so thatthe request link 111 is received and viewed by TPNS 10 withoutmanipulation. Thus, for example, the logic 122 may generate the requestlink 121 for the TPNS 10, by parsing an incoming request link 111,removing a word-type syntax element that represents the proxy domain,and replacing a character marker of the incoming request link with adesignated character that signifies a subdomain to the TPNS 10. Forexample, the incoming link 111 may correspond to“www.proxyservice.newcompany-na1.com” and the link 121 provided for theTPNS 10 may correspond to “www.newcompany.na1.com”.

Absent use of the link structuring logic 120, if any individual level ofthe domain changes in the response from TPNS 10, the proxy server system100 cannot securely communicate with the client 20 without additionalserver certificates being provided to the client. As described ingreater detail, the proxy server system 100 may utilize link structuringlogic 120 to enable exchanges with the client computers 20 to beconducted using a single server certificate 126 (e.g., wildcard SSLcertificate). Specifically, the link structuring logic 120 structuresindividual links containing multiple levels of subdomains to reflect acommon wildcard designation that has one level.

The service interface 130 can include processes to send re-structuredrequest links 121 and session links 125 in the native structure, as wellas to receive generated links 123 in the native structure as part ofcommunication exchanges with TPNS 10. In some examples, the serviceinterface 130 may operate like a browser of a client. In communicatingwith TPNS 10, the service interface 130 may access and use any one of acollection of SSL certificates 135, generated by or for use with TPNS10. As described by other examples, TPNS 10 may utilize subdomains whichseparately require a specific SSL certificate from the requestingbrowser component (e.g., the service interface 130). In an example ofFIG. 1, the service interface 130 may store and utilize the required SSLcertificates 135 in order to receive all, or substantially all of thedata sets in a given response from TPNS 10.

In one implementation, the service interface 130 can send re-structuredrequest links 121 (and session links), having the native structure, toTPNS 10. Initially, the re-structured request links 121 are processed byTPNS 10 to generate one or more responses. The responses 123 from TPNS10 can include content 127 with, for example, embedded session links 125that have the native structure. In response to sending a given requestlink 121, the service interface 130 can assimilate the data setsgenerated by the response of TPNS 10. In some examples, the linkstructuring logic 120 may implement a content configuration component128 which configures the data sets assimilated from the response(s) ofTPNS 10 (e.g., content layout) into configured content 117 which theterminal interface 110 sends to requesting the client computer 20. Theconfigured content 117 may have a proxy-specified format and/orstructure. The configured content 117 may also embed session links 115having the proxy server structure, and corresponding to the embeddedsession links 125 provided in the native structured content 127outputted by the TPNS 10.

The content configuration component 128 may parse content within, forexample, a resource or page assimilated by the service interface 130from the response of TPNS 10, in order to identify links returned fromTPNS 10. The native-to-proxy logic 124 may restructure each link (e.g.,URL) from the native structure to the proxy domain format. Among otherbenefits, the link structuring logic 120 can operate so that allresources (e.g., data sets) delivered to the client 20 include linkswhich, when selected, cause the client to navigate to the proxy serversystem 100.

The link structuring logic 120 may also implement the native-to-proxylogic 124 to convert links provided in the response of TPNS 10 from thenative structure to the proxy domain structure. As described for someexamples, the native-to-proxy logic 124 can parse, for example, embeddedlinks 125 in the content 127 of the response from the TPNS 10, to detectsyntax elements (“.” or (dot)) which signify a subdomain of the networkspace used by TPNS 10. The native-to-proxy logic 124 may replace the(“.” or (dot)) with alternative syntax (e.g., “-” or (hyphen)). Thissubstitution provides a marker representation of the subdomain, but thesyntax itself may not invoke subdomain meaning to the browser of theclient 20.

In response to communicating a given request link 111, the proxy serversystem 100 may return, via the client interface 110, the response 113 inthe proxy-specified structure. In some instances, the response 113 mayinclude, for example, the configured content 117 which correspond todata sets originating from different subdomains of the network spaceused by TPNS 10. The response 113 may include embedded session links115, which are restructured into the proxy domain structure to eliminatesyntax which the client 20 would recognize as being a subdomaindelineation. Thus, for example, the response 113 may include embeddedlinks which may replace “.” (dot) with “-” (hyphen) so as to create alink (e.g., URL) which is interpretable by standard browsers (e.g., suchas used by the client 20) to include a common wildcard designation. Inthis way, the session links 115 returned with the responses 113 for agiven response 123 may be structured to reduce the subdomain componentsto a single subdomain level, which can then be communicated to thebrowser of the client 20 using the wildcard SSL certificate 126, ratherthan multiple SSL certificates which would otherwise be required fromthe client 20. In this way, the client 20 does not need configurationbeyond a standard configuration. Moreover, the user of the client 20 mayselect individual links returned in the response 113 which are in theproxy domain format, thus triggering the communication to pass throughthe proxy server system 100 again, rather than resulting in navigationoutside of the domain of the proxy server system 100.

In the interaction between the client 20 and TPNS 10, the proxy serversystem 100 can be seamlessly integrated to structure the links used bythe client 20 to eliminate, or at least mitigate against the need formultiple SSL certificates by the client 20, in order to processresources identified by the links returned from TPNS 10. Rather, thelinks may be structured to include syntax that specifies a commonsubdomain level, meaning a common wildcard designation may be made foreach subdomain specified by the link or target resource.

By way of an example, the proxy server system 100 may provide a requestlink generated from or for TPNS 10 in a native format as:“system.na1.example.com”. In order to redirect the use of the linkthrough the proxy server system 100, the link may be structured as“system.na1.example.com.proxy-server.com”. Under an example of FIG. 1,the proxy server system 100 may further structure the link so that theclient 20 requires either a single specific certificate, or a wildcardcertificate which is only available for a single subdomain level. Thelink structuring logic 120 of system 100 can structure the above URLinto the following: “system-na1-example-com.proxy-server.com”. Thus, thecharacter designations for subdomains, as provided from TPNS 10, may bereplaced by an alternative character (“-”). With this translation, theclient 20 can process and use the link with a single wildcardcertificate for *.proxy-server.com. With the structuring of the URL, theproxy server system 100 can support any level of subdomains using asingle wildcard certificate.

Examples recognize that links may include parametric information, suchas provided with URL search queries. In some examples, the parametricinformation can be detected and maintained. For example, a search stringon the end of a link which is initially generated in the proxy domainformat may correspond to:system-na1-example-com.proxy-server.com/search_string?query_string. Thesystem parses these individual levels out of the URL.

In some examples, the link structuring logic 120 may structure theindividual links so that the subdomain portion of the link is moved tothe search string portion of the URL:“proxy-server.com/system-na1-example-com/search_string?query_string” canbe translated to or from“system.na1.example.com/search_string?query_string”. Any suchcombination can be made to ensure that the subdomains are recognized bythe proxy server system 100 without requiring additional SSLcertificates.

The proxy server system 100 can structure request links 121 from TPNS 10by moving the portion of the request link which correlates to thesubdomain(s), and then translating the request links to replace thecharacter designations for subdomains. The translation of the requestlinks 121 may be conducted in real-time, to ensure that the content(including the embedded links) from TPNS 10 can be served to individualclient devices using a single certificate (including wildcard). With asingle or wildcard certificate, the client may require zero end-pointconfiguration.

Thus, for example, the proxy server system 100 may perform a parsing andtranslation process at the server level without the use of scripts(e.g., browser executable code) on the client side. The resources whichare provided by the response from TPNS 10 can be parsed to identifylinks which are then restructured to utilize the proxy domain format.The restructuring ensures that all communications from the client deviceare sent to the location of the proxy server system 100 and not to theoriginal destination.

Methodology

FIG. 2 illustrates a method for operating a proxy server, according toone or more embodiments. A method such as described with an example ofFIG. 2 may be implemented using a proxy server system such as describedwith an example of FIG. 1. Accordingly, reference is made to elements ofFIG. 1 for purpose of illustrating suitable components for performing astep or sub-step.

In one implementation, the proxy server system 100 is set to operate ina suffix mode and provided with the domain used as the suffix (210). Theproxy server system 100 may further be deployed in a network environmentwhere multiple clients are able to use, for example, browsers to accessthe proxy server system 100. The clients 20 may access the proxy serversystem 100 in order to receive services from TPNS 10.

When a given client seeks to access TPNS 10, the proxy server system 100may receive a URL on the domain (220). The proxy server system 100receives the URL and removes a domain component from the URL. The proxyserver system 100 may also pack the URL to include alternative syntax,for example, “-” for syntax that designates subdomains “.”, so that theURL is structured to include a single subdomain. This can be performedby the proxy server system 100 at the proxy level by parsing the URL andmatching the URL into a suffix proxy format.

When a client 20 communicates back to the proxy server system 100, theclient translation process is performed (230). This may includefollowing a URL, a subdomain portion of the URL is unpacked, and asyntax conversion is performed to replace the alternative syntax of thepacked URL (e.g., ‘-’ (hyphen)) back into a ‘.’ (dot), which is astandard domain separator within a URL. Conversely, then the response isprovided by the TPNS 10, the service side translation process may beperformed to structure or pack URLs, as described with examples above(240).

Through the structuring of the URLs exchanged between the client 20, theproxy server system 100 and TPNS 10, the proxy server system 100 canenable a single SSL certificate or wildcard SSL certificate to beemployed for the client. In this way, the clients are able to receivethe enhanced functionality and benefits of the proxy server system 100,without requiring endpoint configuration which is typical underconventional approaches.

In the case where the original URL contains a ‘-’ or other structuringcharacter, a host-mapping filter or similar solution can be used. Thehost-mapping filter can be selected to specify an original domain sothat it is not unpacked to identify a subdomain. For example,“sub-domain.example.com” may be unpacked to “sub-domain.example.com”rather than “sub.domain.example.com”.

The proxy server system 100 may be implemented as an intermediarybetween one or more clients 20 and TPNS 10. TPNS 10 may correspond to,for example, a cloud service, a SaaS or a web-based application orservice.

Each network request sent by the client 20 through the proxy serversystem 100 may be examined. If any suffix domain is detected, the proxyserver system 100 can initiate performance of the link structuringprocess, as described with an example of FIG. 1.

Likewise, a network request that is sent from the client 20 to the proxyserver system 100 may have the suffix removed when processed by theproxy server system 100. Furthermore, the proxy server system 100 mayunpack the URL into its original or native format. This process may alsobe performed in real-time.

A network response that is sent from the proxy server system 100 to theclient 20 may include the suffix applied, and the original URL packed soas to remove syntax that marks subdomains. The proxy server system 100may perform this operation in real-time, so that the original content ofthe response does not need to have addresses rewritten in files orscripts, or be modified.

The proxy server system 100 may implement processes to ensure that thecontent of the resource when packed is “unpacked”/reformatted back tohow it was originally presented by TPNS 10, SaaS or web application soas to not break compatibility with said end application.

The Example cloud application may be being used by an organization. Thedomain in use to access services may be system.na1.salesforce.com

Here, “system” and “na1” are subdomains; “salesforce” is the rootdomain; and “conn” is the TLD.

SSL certificates issued to Salesforce by a recognized certificateauthority allow the organization to access this site securely in abrowser.

The organization uses a proxy computer system to route traffic through adomain under their control. (e.g., stratokey.com). A full suffix domainmay then appear as system.na1.salesforce.com.stratokey.com

Here, “system”, “na1”, “salesforce” and the first “conn” are allsubdomains; “stratokey” is the root domain; the last “conn” is the TLD.

In this situation, the organization that controls the stratokey.comdomain must be issued SSL certificates to allow secure access by anybrowser.

The options for the organization are to obtain a certificate for everycombination of subdomain that could be used or obtain a “wildcardcertificate”, which is one that allows any value, but only for the firstsubdomain component in a URL.

Examples recognize that these options may not be feasible for anorganization, as the subdomains in use are not under the control of theorganization, and additional subdomains could be added by theapplication provider at any point in time.

When structuring is performed by the suffix proxy, some examples providethat the ‘.’ characters are replaced in the entire original URL withreplacement characters. As described with other examples, thereplacement characters may include “-” so that the preceding examplebecomes system-na1-salesforce-com.stratokey.com

In this way, the original URL appears as a single subdomain and awildcard SSL certificate can be issued for *.stratokey.com

A user in an organization which utilizes the proxy server system 100 maynavigate to system-na1-salesforce-com.stratokey.com and the suffix proxyserver will communicate with the original URL atsystem.na1.salesforce.com, in a manner that is seamless to the user.

In some variations, the proxy server system 100 can also operate inmodes where the entire subdomain portion of a URL for a third-partynetwork service is pre-mapped to a shortened packed subdomain. Forexample system.na1.salesforce.com may be mapped internally to “sysna1ns”which is then translated at the proxy server into“system.na1.salesforce.com”. In such variations, the proxy server system100 may perform such processes dynamically at the proxy server levelwithout requiring any client side script injection.

The suffix proxy structuring also supports translating subdomain levelsinto both paths and query strings of a URL. For example the URL“system.na1.salesforce.com” can be translated into“example.com/system-na1-salesforce-com/” or“example.com?p=system-na1-salesforce-com”.

FIG. 3 illustrates a proxy computer system that implements contentcontrol with respect to access by client computers of a third-partynetwork service. In particular, a proxy computer system 300 may beimplemented using a server, or combination of servers, to receive andforward communications between the group of client computers 20 (e.g.,operating as part of the enterprise network 14) and the TPNS 10. Each ofthe client computers 20 may correspond to, for example, an end userterminal, work station or other computer system capable of communicatingwith the proxy computer system 300 over the World Wide Web and/or otherdata networks.

According to some examples, the system 300 includes a client interface310, a communication modification component 320 and a service interface330. The client interface 310 can provide for the exchange of proxycommunications with individual client computers 20 of the enterprisegroup. The modification component 320 may modify outgoing communications(e.g., client communications 311) that originate from client computers20 and are intended for the TPNS 10, as well incoming communications(e.g., TPNS response 333) that originate from the TPNS 10 in response tothe requests of the respective requesting client computers 20.

As described with an example of FIG. 1, the client interface 310 mayreceive client communications 311 for content from individual clientcomputers 20. In some implementations, the client communication 311includes, for example, request links 111 (see FIG. 1) and/or sessionlinks 115 (see FIG. 1), such as described with an example of FIG. 1. Insome variations, the client communications 311 can include or otherwisespecify data and content submissions, such as field data and/orattachments (e.g., documents or other files).

The modification component 320 includes components to modify clientcommunications 311 that are received by the system 300 and are intendedfor the TPNS 10, as well as TPNS responses 333 that are received by thesystem 300 from the TPNS 10 and are intended for a correspondingrequesting client computer 20. In an example, the modification component320 includes one or more types of link structuring logic 316 torestructure links provided with the TPNS response 333, for therequesting client computer 20. For example, the link structuring logic316 may be implemented as described with an example of FIG. 1 (e.g., seelink structuring logic 120), to unpack request links 111 (FIG. 1) and/orsession links 115 (FIG. 1), such that client communications 311 can bereceived and restructured by the system 300 for communication to theTPNS 10. Thus, as described with examples of FIG. 1, the linkstructuring logic 316 may restructure links of client communications 311and of TPNS responses 333, in order to reduce or otherwise mitigate aneed for certificates by the respective client computers 20.

As an addition or variation, the modification component 320 may includeencryption logic 322 and decryption logic 324. The encryption logic 322can layer-in encryption of data that is included or otherwise providedwith client communications 311. By way of example, the clientcommunications 311 can include field data and/or file attachments, whichthe encryption logic 322 may encrypt in real-time, before the serviceinterface 330 sends corresponding TPNS communications 331 to the TPNS10. In some examples, the system 300 handles all client communications311 originating from the client computers 20 to the TPNS 10. Thus, thesystem 300 can provide an enterprise 14 of clients 20 with an additionalenhancement of encrypting data fields, attachments, and otherinformation included with the client communications 311.

Still further, in some examples, the system 300 selectively encryptsdata of client communications 311 before sending modified communications331 to the TPNS 10. For example, the modification component 320 may bepreconfigured to recognize certain data fields and types orclassifications of data items as being sensitive. Based on suchdeterminations, the encryption logic 322 can selectively encrypt suchdata fields, types or classifications, such that the TPNS 10 receivesTPNS communications 331 that include encrypted data originating from theclient computers 20.

The service interface 330 can send the TPNS communication 331 to theTPNS 10, and receive corresponding TPNS responses 333 from the TPNS 10.As described with an example of FIG. 1, the TPNS response 333 mayinclude, for example, restructured links 121 (see FIG. 1) and sessionlinks 125 (see FIG. 1) which are unpacked and otherwise converted into anative format of the TPNS 10. The TPNS response 333 may also beencrypted in whole or in part. In an example, the TPNS response 333 mayinclude content which was subject to encryption by the encryption logic322.

As described in greater detail, the modification component 320 may alteror otherwise modify the TPNS responses 333. For example, as describedwith an example of FIG. 1, the link structuring logic 316 may packsession links 125 (see FIG. 1) provided with the response from the TPNS10, as described with an example of FIG. 1 (e.g., see link structuringlogic 120). By unpacking links embedded in communications 311 fromindividual client computers 20, and packing links provided with 333 tosend to respective client computers 20 as response communications 313,the system 300 can utilize wildcard designations as between clientcomputers 20 and the system 300 in order to reduce the number ofcertificates which individual client computers would otherwise need tocommunicate with and receive services from the TPNS 10.

In some examples, the decryption logic 324 of the modification component320 can decrypt encrypted portions of the TPNS response 333. Forexample, the decryption logic 324 can process each TPNS response 333 ofthe TPNS 10 to decrypt content which was previously encrypted by theencryption logic 322. As an addition or variation, the decryption logic324 may decrypt content that was encrypted by the TPNS 10 or anothersource.

According to some examples, the modification component 320 includes aparsing component 318 to parse the content of the TPNS response 333 toidentify sensitive content elements, or portions thereof. The parser 318may scan the content of the TPNS response 333 for one or more markersthat are indicative of elements or portions of the return content beingsensitive. In an example, the parser 318 can detect encrypted portionswithin the content of the TPNS response 333. In variations, the parser318 may detect other markers associated with sensitive or protectedcontent, with respect to data elements that are embedded within thecontent of the TPNS response 333. For example, the parser 318 mayrecognize certain fields of a form that is returned as part of the TPNSresponse 333 as inherently containing sensitive data or information,even when other fields of the form are not recognized as beingsensitive. When the parser 318 identifies a portion of the content ofthe TPNS response 333 to include sensitive portions or elements, themodification component 320 may implement content handling logic 326 todetermine how the sensitive portions or elements are to be provided tothe requesting client computer 20.

In an example, the content of the TPNS response 333 includes one or moreencrypted portions (e.g., data fields). The modification component 320parses the content of the TPNS response 333 to identify encrypted data.When a portion of the TPNS response 333 is identified to be encrypted,the modification component 320 utilizes the content handling logic 326to decrypt the selected encrypted portions of the content.

In some variations, the content handling logic 326 determines an action,or a series of actions which are to be performed with respect to contentof the TPNS response 333. In some implementations, the content handlinglogic 326 can provide for a default set of actions (e.g., decryptencrypted data elements), as well as one or more alternative set ofactions if a predetermined condition or criterion (or set of criteria)are met.

With respect to the examples provided, the content handling logic 326may include rules or other logic which determine the handling of thesensitive data based at least in part on (i) a type, classification, orother categorization of the data elements included with the TPNSresponse 333, and/or (ii) a risk assessment of the requesting client (orclient that generated the client communication 311, to receive thecorresponding TPNS responses 333). In examples in which the content ofthe TPNS response 333 includes sensitive or encrypted portions, themodification component 320 may implement the content handling logic 326to determine whether the response communication 313 to the requestingclient is to follow a default process or an alternative process. Therisk assessment profile may be in the form of a score, or as one or morepredefined quantifiable metrics that are deemed relevant to evaluatingunwanted risks which may be associated with a requesting client, such as(i) the requesting client 20 (or its user) being unauthorized to receivethe sensitive data, (ii) the requesting client 20 (or its user) being animposter, and/or (iii) the requesting client 20 being unprotected orotherwise having poor security integrity.

According to some examples, the modification component 320 utilizes ausage monitor 328 to determine information relating to a usage profileassociated with individual client computers 20. The usage monitor 328may execute on the system 300 to aggregate and statistically analyzeproxy-based data that is indicative of user behavioral traits, such as(i) access times during the course of a typical day during which theclient and/or the user of the client accesses the proxy computer system300 and/or the TPNS 10; (ii) data usage of the client computer 20 and/orthe associated user of the client, with respect to the system 300 and/orthe TPNS 10; and/or (iii) network locations, devices or physicallocations where the client computer 20 and/or associated user accessedthe system 300 and/or the TPNS 10. In variations, the usage monitor 328may be implemented as a separate component or service of anotherthird-party, or of an enterprise network 14 of the client computers 20.Still further, in variations, the usage monitor 328 can be implementedat least in part by a client application, program, plug-in or process.Still further, the modification component 320 may utilize multiple usagemonitors, such as a combination of a local or client base monitor thatdetects certain types of uses activity, and a network-based usagemonitor that detects other types of activity. Additionally, the usagemonitor 328 may retrieve usage information from multiple sources, suchas from the browser history of individual client computers 20.

In some variations, the modification component 320 implements the usagemonitor 328 to obtain a risk assessment score 325 (or other metric) thatquantifies a probability of an unwanted risk with respect to therequesting client. Depending on the type of data being accessed andimplementation, the usage monitor 328 may generate the risk assessmentscore 325 as a real-time metric, based on current or very recent usageprofile information about the requesting client 20, or its associateduser. The content handling logic 326 can select an action (or series ofactions) that the system 300 is to perform with respect to the sensitivecontent element, based at least in part on the risk assessment score325. As an addition or variation, the content handling logic 326 canselect the action or series of actions based on a type, classificationor other characteristic of the content portions of the TPNS response333.

For content provided with the TPNS response 333 for a given transaction,the content handling logic 326 may implement the default process if therisk assessment score 325, which may be determined for the requestingclient computer 20, indicates a risk level that is below a giventhreshold. Likewise, the content handling logic 326 may implement thealternative process if the risk assessment 325 score indicates the risklevel for the requesting client computer 20 is above the giventhreshold. Under the default process, the modification component 320 mayutilize the decryption logic 324 to decrypt the encrypted portions ofthe TPNS response 333. The client interface 310 may then send theresponse communication 313 to the requesting client 320, with contentdata that has been decrypted. Under the alternative process, themodification component 320 may send a response communication 313 to therequesting client without decrypting the encrypted data elements orportions. As an alternative or variation, the modification component 320may remove or otherwise mask (e.g., replace the encrypted content withfiller content) the sensitive or encrypted portions of the responsecommunication, so that the requesting client 20 does not have access toeven an encrypted form of the sensitive content.

In some variations, multiple threshold levels may be utilized withrespect to the risk assessment score 325, and the modification component320 may select inaction, or one or more series of actions based on theparticular risk level of the client computer 20. For example, in avariation, if the risk assessment score 325 of the requesting client 20indicates a risk level that is below a first threshold that is deemedsafe, but above a second threshold that is deemed as likely to becompromised, the requesting client 20 may receive the responsecommunication 313 with sensitive data elements being encrypted. In suchan example, a user of the client computer 20 may have ability to decryptthe encrypted data elements using, for example, a previously stored key,or through an additional authentication process. If however, the riskassessment score 325 of the requesting client 20 indicates a risk levelthat is indicative of the client computer likely being compromised, themodification component 320 may provide the response communication 313with the sensitive data elements being removed entirely.

Still further, in some examples, the parser 318 may parse the content ofthe TPNS response 333 in order to determine links to target resourceswhich are otherwise suitable for direct access by the requesting client20. The link structuring logic 316 may include logic to structure (orrestructure) such identified links as direct links 317 that areselectable on the client computer 20 to directly access the respectivetarget resource (e.g., page, form, etc.). By direct access, a clientrequest from the requesting client computer 20 can select the directlink 317 to accesses the target resource through the TPNS 10 (or othernetwork service), and without use of the system 300.

In some examples, the parser 318 of the modification component 320parses the target resource of the TPNS response 333 to identify contentelements which are of a particular type or classification. For example,the parser 318 may identify, from the content of the TPNS response 333,links which locate content elements of one or more predetermined types(e.g., Cascading Style Sheets (CSS), JavaScript or other scripts, imageresources, etc.). The parser 318 may detect such content based on, forexample, the extension accompanying the file name of individual links inthe TPNS response 333.

Upon the parser 318 detecting such links, the link structuring logic 316embeds a direct link 317 to the target resource within the responsecommunication 313. Conversely, for other types of target resources(e.g., HTML/XHTML), the link structuring logic 316 may generate proxylinks 319, such as packed session links (e.g., packed session links 115,in FIG. 1).

The modification component 320 may generate the response communication313 to include, for example, direct links 317, along with proxy links319. If the requesting client 20 subsequently selects the direct link317, the requesting client 20 may access the corresponding targetresource on the TPNS 10 directly, without passing the request throughthe system 300. If, on the other hand, the requesting client 20 selectsthe proxy link 319 from the response communication 313, the subsequentclient communication 311 is directed to the system 300.

In some examples, the modification component 320 can utilize the contenthandling logic 326 to determine whether a link to a target resource of apredetermined type or classification is to be structured as a directlink 317 with the response communication 313. The content handling logic326 can implement a dynamic determination based on, for example, theload on the system 300. In such an implementation, the system 300 mayincrease the number of data types or classifications which can behandled through direct links, such that a greater number of direct linksare used when there is more load (e.g., traffic) on the system.

As an addition or alternative, when candidate direct links 317 are foundin the TPNS response 333, the content handling logic 326 may probe thetarget resources that are located by such direct links 317 forsuitability, such as to determine whether the respective targetresources are available, and not characteristic of content that issensitive. For a given candidate direct link, if the target resource isnot available, or otherwise deemed to be sensitive, the content handlinglogic 326 may cause the link structuring component 316 to generate aproxy link 319 for the target content. If the client 20 subsequentlyrequests the proxy link 319, the resulting client communication 311passes through the system 300, where, for example, the target resourcecan be encrypted.

By way of example, the TPNS response 333 may include:

<script type=“javascript” src=“/etc/clientlibs/granite/jquery.min.js”/>

If the content handling logic 326 implements a mode to enable directlinks, then the link structuring component 316 may generate thefollowing link for inclusion in the response communication 313: <scripttype=“javascript”src=“https://salesforce.com/etc/clientlibs/granite/jquery.min.js”/>

If the content handling logic 326 implements a mode to disable thedirect links 317, then the link structuring component 316 may generatethe following packed link for inclusion in the response communication313: <script type=“javascript”src=“https://www.example.com/salesforce-com/etc/clientlibs/granite/jquery.min.js”/>

FIG. 4 illustrates an example method for operating a proxy service toselectively decrypt content returned by a third-party network service.FIG. 5 illustrates an example method for operating a proxy service toselectively provide direct links for client computers to bypass theproxy service.

Example methods such as described with FIG. 4 or FIG. 5 may beimplemented using, for example, a proxy service system such as describedwith an example of FIG. 3. Accordingly, reference may be made toelements of FIG. 3 for purpose of illustrating suitable components forperforming a step or sub-step being described.

With reference to FIG. 4, the system 300 receives content intended for arequesting client computer from the TPNS 10 (410). The content mayinclude a sensitive portion, such as a protected (e.g., encrypted) setof data elements. In some examples, the system 300 scans contentreturned by the TPNS 10 for data elements or portions which werepreviously encrypted by the system 300, when such content was sent by acorresponding client computer 20 to the system 300 for forwarding to theTPNS 10 (412).

The system 300 makes a determination as to whether a protected portionof content provided by the TPNS 10 is to be decrypted for a requestingclient computer 20 (420). The activity or usage of the requesting clientcomputer may be ascertained.

The system 300 may send the content returned by the TPNS 10 to therequesting computer in a structure or form that is based on thedetermination (430). For example, the determination may be based atleast in part on determining whether a risk metric associated with theuser's current or past activity exceeds a predetermined threshold (432).If the risk metric indicates a risk level that exceeds the predeterminedthreshold level, the system 300 may send the content returned by theTPNS 10 in encrypted form, or alternatively, in masked form (e.g.,content is removed or replaced by other non-sensitive content). If, onthe other hand, the risk metric indicates a risk level that is less thanthe predetermined threshold level, the system 300 may decrypt thecontent returned by the TPNS 10, and then send the decrypted contentreturned by the TPNS 10 to the requesting client computer 20.

With reference to FIG. 5, the system 300 retrieves content requested bya client computer from the TPNS 10 (510). The system 300 parses theretrieved content to detect a set of links (520).

For each link in the set, a determination is made as to whether the linklocates a corresponding resource that is of a preselected set of one ormore types (530). For example, the system 300 may scan the retrievedcontent to identify resources which have markers that are indicative ofselect data types, such as extensions corresponding to scripts (orscript files) (e.g., is′), as well as ‘ccs’ files or image files.

If the corresponding resource located by the link is of the preselectedtype, the system 300 structures the link as a direct link that isselectable by the requesting client computer 20 to bypass the proxyservice and to directly retrieve the corresponding resource (540).

The system 300 may provide the client computer with resource that isbased on content retrieved from the TPNS 10, and which includes thedirect link that locates the corresponding resource of the preselectedset (550).

Hardware Diagrams

FIG. 6 is a block diagram that illustrates a computer system upon whichembodiments described herein may be implemented. For example, in thecontext of FIG. 1 and FIG. 3, the respective proxy computer system 100,300 may be implemented using a computer system such as described by FIG.6. The proxy computer systems 100, 300 may also be implemented using acombination of multiple computer systems as described by FIG. 6.

In one implementation, a computer system 600 includes processingresources 610, a main memory 620, a read only memory (ROM) 630, astorage device 640, and a communication interface 650. The computersystem 600 includes at least one processor 610 for processinginformation and the main memory 620, such as a random access memory(RAM) or other dynamic storage device, for storing information andinstructions to be executed by the processor 610. The main memory 620also may be used for storing temporary variables or other intermediateinformation during execution of instructions to be executed by theprocessor 610. The computer system 600 may also include the ROM 630 orother static storage device for storing static information andinstructions for the processor 610. A storage device 640, such as amagnetic disk or optical disk, is provided for storing information andinstructions, including instructions 642 for implementing the exampleproxy computer systems 100 and 300. Additionally, the processor 610 canexecute the instructions 642 to implement methods such as described withexamples of FIGS. 2, 4 and 5.

The communication interface 650 can enable the computer system 600 tocommunicate with one or more networks 680 (e.g., cellular network)through use of the network link (wireless or wireline). Using thenetwork link, the computer system 600 can communicate with, for example,client computers 20, servers and one or more third-party networkservices 10.

The computer system 600 can also include a display device 660, such asan LCD monitor, or a television set, for example, for displayinggraphics and information to a user, or no display device at all as withsome servers. One or more input mechanisms 670, such as a keyboard thatincludes alphanumeric keys and other keys, can be coupled to thecomputer system 600 for communicating information and command selectionsto the processor 610. Other non-limiting, illustrative examples of inputmechanisms 670 include a mouse, a trackball, touch-sensitive screen, orcursor direction keys for communicating direction information andcommand selections to the processor 610 and for controlling cursormovement on the display 660.

Examples described herein are related to the use of the computer system300 for implementing the techniques described herein. According to oneembodiment, those techniques are performed by the computer system 300 inresponse to the processor 610 executing one or more sequences of one ormore instructions contained in the main memory 620. Such instructionsmay be read into the main memory 620 from another machine-readablemedium, such as the storage device 640. Execution of the sequences ofinstructions contained in the main memory 620 causes the processor 610to perform the process steps described herein. In alternativeimplementations, hard-wired circuitry may be used in place of or incombination with software instructions to implement examples describedherein. Thus, the examples described are not limited to any specificcombination of hardware circuitry and software.

It is contemplated for examples described herein to extend to individualelements and concepts described herein, independently of other concepts,ideas or system, as well as for examples to include combinations ofelements recited anywhere in this application. Although examples aredescribed in detail herein with reference to the accompanying drawings,it is to be understood that the concepts are not limited to thoseprecise examples. Accordingly, it is intended that the scope of theconcepts be defined by the following Claims and their equivalents.Furthermore, it is contemplated that a particular feature describedeither individually or as part of an example can be combined with otherindividually described features, or parts of other examples, even if theother features and examples make no mentioned of the particular feature.Thus, the absence of describing combinations should not preclude havingrights to such combinations.

What is claimed is:
 1. A proxy computer system comprising: a memoryresource to store a set of instructions; one or more processors toaccess the set of instructions from the memory resource to communicatewith each of a client computer and a third-party network service, and toprovide a proxy service for the client computer to utilize thethird-party network service; wherein the one or more processors providethe proxy service by: retrieving content requested by the clientcomputer from the third-party network service; identifying a set of filetypes for files linked within HTML content that are suitable for directaccess by the client computer; parsing the content to detect one or morelinks; for each of the detected one or more links, determining whetherthe link locates a corresponding resource of the set of file types;generating modified content based on said determining, the modifiedcontent comprising, (i) for at least one link of the detected one ormore links that locates a corresponding resource of the set of filetypes, a direct link that includes an absolute domain address of thethird-party network service to enable the client computer to bypass theproxy service and directly retrieve the corresponding resource from thethird-party network service, and (ii) for at least one link of thedetected one or more links that locates a corresponding resource of adifferent file type, a proxy link that does not bypass the proxyservice; and providing the modified content to the client computer. 2.The proxy computer system of claim 1, wherein the set of file typesincludes a cascading style sheet (CCS) file, image file or a scriptfile.
 3. The proxy computer system of claim 1, wherein suitability ofone or more file types of the set of file types is based on sensitivityof the corresponding content.
 4. The proxy computer system of claim 1,wherein the one or more processors parse the content to identifyindividual links that include a marker associated with the correspondingresource of the set of file Noes.
 5. The proxy computer system of claim4, wherein the one or more processors probe the corresponding resourceof the individual links to determine a handling of the link.
 6. Theproxy computer system of claim 5, wherein the one or more processorsprobe the corresponding resource of the individual links to determinewhether to restructure the link as the direct link or as a proxy link.7. The proxy computer system of claim 1, wherein the one or moreprocessors structure the link as the direct link that includes anoriginal format provided by the third-party network service.
 8. Theproxy computer system of claim 1, wherein the one or more processors:determine a load on the proxy computer system; and based on an increasein the load on the proxy computer system, add one or more file types tothe set of file types to increase a number of direct links handled bythe third-party network service without involving the proxy computersystem.
 9. A method for providing a proxy service for a third-partynetwork service, the method being implemented by one or more processorsof a network computer system and comprising: retrieving content,requested by a client computer, from the third-party network service;identifying a set of file types for files linked within HTML contentthat are suitable for direct access by the client computer; parsing thecontent to detect one or more links; for each of the detected one ormore links, determining whether the link locates a correspondingresource of the set of file types; generating modified content based onsaid determining, the modified content comprising, (i) for at least onelink of the detected one or more links that locates a correspondingresource of the set of file types, a direct link that includes anabsolute domain address of the third-party network service to enable theclient computer to bypass the proxy service and directly retrieve thecorresponding resource from the third-party network service, and (ii)for at least one link of the detected one or more links that locates acorresponding resource of a different file type, a proxy link that doesnot bypass the proxy service; and providing the modified content to theclient computer.
 10. The method of claim 9, wherein the set of filetypes includes a cascading style sheet (CCS) file or a script file. 11.The method of claim 9, wherein suitability of one or more file types ofthe set of file types is based on sensitivity of the correspondingcontent.
 12. The method of claim 11, further comprising parsing thecontent to identify individual links that include a marker associatedwith the corresponding resource of the set of file types.
 13. The methodof claim 12, further comprising probing the corresponding resource ofthe individual links to determine a handling of the link.
 14. The methodof claim 13, wherein probing the corresponding resource of theindividual links includes determining whether to restructure the link asthe direct link or as a proxy link.
 15. The method of claim 9, whereinstructuring the link as the direct link includes providing the link tothe requesting client computer in an original format provided by thethird-party network service.
 16. The method of claim 9, furthercomprising: determine a load on the network computer system; and basedon an increase in the load on the network computer system, add one ormore file types to the set of file types to increase a number of directlinks handled by the third-party network service without involving thenetwork computer system.
 17. A non-transitory computer-readable mediumthat stores instructions, which when executed by one or more processorsof a network computer system, cause the network computer system toprovide a proxy service for a client computer to utilize a third-partynetwork service and perform operations that include: retrieving contentrequested by the client computer from the third-party network service;identifying a set of file types for files linked within HTML contentthat are suitable for direct access by the client computer; parsing thecontent to detect one or more links; for each of the detected one ormore links, determining whether the link locates a correspondingresource of the set of file types; generating modified content based onsaid determining, the modified content comprising, (i) for at least onelink of the detected one or more links that locates a correspondingresource of the set of file types, a direct link that includes anabsolute domain address of the third-party network service to enable theclient computer to bypass the proxy service and directly retrieve thecorresponding resource from the third-party network service, and (ii)for at least one link of the detected one or more links that locates acorresponding resource of a different file type, a proxy link that doesnot bypass the proxy service; and providing the modified content to theclient computer.
 18. The non-transitory computer-readable medium ofclaim 17, wherein the set of file types includes such as a cascadingstyle sheet (CCS) file, image or a script file.
 19. The non-transitorycomputer-readable medium of claim 17, wherein suitability of one or morefile types of the set of file types is based on sensitivity of thecorresponding content.
 20. The non-transitory computer-readable mediumof claim 19, wherein the one or more processors further executeinstructions, which cause the network computer system to performoperations that include: determining a load on the proxy computersystem; and based on an increase in the load on the proxy computersystem, adding one or more file types to the set of file types toincrease a number of direct links handled by the third-party networkservice without involving the proxy computer system.